Havocscope calculates the world’s prostitution revenue by adding up the estimated market values from countries where prostitution revenue is available. The revenue estimates comes from a wide range of sources, such as public health programs, law enforcement initiatives and other criminal justice programs, as well as media reports.

It's big business. Revenue generated by paying for sex totals $186 billion around the world, which is so big it actually dwarfs the Powerball jackpot. China easily tops the list, which makes sense considering five million people work in the sex trade.